Ok similar purposes



'2 Sheets-Sheet 1.

(NowModeL) E. M. PRITCHARD. COMPOSITE MATERIAL FOR ROOFING OR SIMILARPURPOSES. No. 513,247} Patented Jan. 23, 1894 I H 1 1 MW q, s 1 f I Q Gx W I E a l 0 I G. M I M I M .1 0 v 0 I U a M w. .A Z V M (No Model.) 2Sheets-Sheet '2.

- E. M. PRITOHARD. COMPOSITE MATERIAL FOR ROOFING 0R SIMILAR PURPOSES.

No. 513,247. a Patented J an. 23,1894.-

a/ 7 Q Q d/ x 2 1 w #51 W QZ fl 1% E $2 4 4 G a y E? @Zf Elnnnnnnnnnnnnn c containing my invention.

UNrrEo' STAT-Es PATENT Option.

EZEKIEL M. PRITOHARD, OF NEWV YORK, N. Y.

COMPOSITE MATERIAL FOR ROOFING OR SIMILAR PURPOSES.

$PECEFICATION forming part of Letters Patent No. 513,247, dated January23, 1894.

Application filed March 1, 1893- Serial No. 4641 (N0 dem To all whom itmay concern.-

Be it known that I, EZEKIEL M. PRITCHARD, a citizen of the UnitedStates, residing at New York city, in' the county of New York and Stateof New York, have inventedcerlain new and useful Improvements inComposite Material for Roofing and Similar Purposes, of which thefollowing is a specification, reference being had therein to theaccompanying drawings.

Figure 1 is an elevation of a paneled door Fig. 2 is a section on line03 00, Fig. 1, enlarged. Fig. 3 is a section, also enlarged, on line yy, Fig. 1, but having added thereto door jambs including moldings. Fig.4 is an elevation of a plain, flat door, without panels, parts beingbroken away. Fig. 5 is a section on line 2 2 Fig. 4.. Fig. 6 is anenlarged.- view of the lower part of Fig. 5. Figs. 7, 8, and 9 aredetails illustrating the construction of different parts shown in Fig.3.

The object of this invention is to improve the construction of variousparts of buildings into which wood usually enters as a material to theend that such portions of the structure shall effectually resist anytemperature to which they may be ordinarily subjected, withoutundergoing destruction; without transmitting heat to adjacent parts of abuilding in such degree as to cause ignition; and without undergoingsuch change of form or dimensions as will permit the passage of heatedair, the heated products of combustion, water or steam, or heat in anyother form, in such quantity as to be objectionable. In order to meetthe above requirements it is desirable that the material employedv shallbe comparatively inexpensive; shall not be of excessive weight; shallnot be subject to great changes in dimension by expansion or contractionunder varying temperatures, or under such different conditions ofmoisture as they will be ordinarily subjected to; and. shall not beliable to be warped under the varying conditions of heat or moisture towhich it will be subjected. It is also important that such materialshall be capable of being made in, a great many different forms orconfigurations,

such as are usually employed in architectural designs for buildings andother structures. It is well known that neither metal alone, nor incombination with a material which is a good non-conductor of heat willanswer for the uses above indicated; because, among other things, it isliable to be warped by heat, especially when its temperature is suddenlylowered by the application of water, as frequently occurs during fire ineither the building where such material is used or in an adjacentbuilding. Another objection to such use is that when wood is covered onone or both sides with sheet metal it has been found practicallyimpossible to prevent combustion of the wood under rather hightemperatures, the requisite amount of air obtaining accessnotwithstanding the presence of the sheet metal covering.

One part of this invention consists, essentially, of the combinationwith sheet metal plates, of a central supporting sheet or strip in thenature of a core having sufficient rigidity or stiffness to resistbending under ordinary circumstances, with interposed sheets of fibrousor other flexible non-conducting material arranged between the centralsheet or strip and the sheet metal plate or plates on one or both sides(as the case may be) of the sheet or strip.

As one mode of carrying out this invention is illustrated in detail inFigs. 4, 5and6,Iwould refer to those figures. A, B, represent thecentral sheet or strip, which, in this instance, I have represented asbeing of thin boards preferably glued together, and of which the grainin the one marked A runs up and down (lengthwise) while the grain of theboard B runs crosswise to that of the board A, as is indicated clearlyin Fig. 6, it being well understood among wood Workers that by such adisposition of the material great firmness and rigidity are obtained inproportion to the quantity of wood used. While ordinarily a two-plycomposite central sheet or core will answer every purpose where moderatelinear dimensions are required; yet, Where larger area is to be used, Iwould recommend three or four ply, each ply being rather thin in orderto avoid excessive weight. So, also, the central sheet may be cleated ifdesired to secure increased stiffness. O, 0, represent layers or sheetsof some suitable non-conducting material which is adapted forapplication to the sides, and preferably to the edges, of the centralsheet or strip. I prefer to use, for this purpose, asbestus in sheetssubstantially as it is produced in the ordinary manufacture; and,preferably, with little or no admixture of foreign material. Such sheetsof as bestus are especially desirable for this use because among otherreasons, of its flexibility which facilitates its being made easily toconform to surfaces of irregular outline; and, further, by reason of itspossessing a certain amount of compressibility and elasticity, as willbe hereinafter explained. D d d represent strips or plates of sheetmetal, preferably tin, sheet iron, or galvanized iron, of which thereare enough in number and length to extend entirely around, and inclose,the edges of the central sheet and the interposed asbestus appliedthereto, with the turned over edges d d overlapping the asbestus whichis upon the opposite sides of the central sheet, as is plainly indicatedin Figs. 4 and 6. In applying these metal edge-plates, as I prefor tocall them,I propose to first bend the edges of the metal over towardeach other into U shape forming flanges cl'd which are practicallyparallel to each other and about far enough apart to fit closely theouter surfaces of the asbestus upon the sides of the central plates. Tofacilitate putting them in place, these flanges may be, when first made,a little flaring outwardly to facilitate putting them in positionwithout disturbing the asbestus which they overlap. E, E, are sheets ofmetal of such size as to practically correspond in both directions withthe dimensions of the sides of the central sheet; although I usuallymake them a little smaller so that all of their edges shall fall alittle inside of the portions D of the edge strips. When it is notpracticable to obtain sheets E of proper size they may be made up ofsmaller sheets, preferably joined aftheir edges by interlocking. F, F isa series of bolts passing through all of the above referred to parts,and binding them firmlytogether. In these figures (4, 5, and 6) I haveshown my invention in the form of a door. Around the edges of the doorthe bolts should be close enough together so that the metal plates canbe clamped ordrawn toward the central sheet and toward each other with agrip sufficient to so compress the asbestus as to form joints which,while they are not absolutely air tight perhaps, approachsufficientlyclose thereto so that they will practically exclude air from contactwith the central sheet, while permitting the escape therefrom of anyvapors or gases which may be produced by the action of heat of suchcharacter as they may be subjected to during ordinary use. It will ofcourse be understood that owing to the porosity of the sheets ofasbestus such vapors or gases can pass outward through the asbestus andbetween the adjacent surfaces of metal with but slight internalpressure, even though the parts fit so closely that practically no aircan enter framed together in any usual or approvedmanner. Within thelast referred to parts of the door the space is divided by a frieze railL and mountings M M to assist in supporting the frieze panels or squarepanels N N, the

standing panels 0 O and lying panels or panels P as may be preferred. Inorder to protect a door of this character from burning I propose tocover its sides and edges with sheets of asbestus C or othernon-conducting material, together with plates or sheets of thin metalstamped or swaged into suitable shape having raised portions such aswill conform substantially to the configuration produced by the panelingabove described, and so that by the use of fastening devices such asclamping bolts F or their equivalents, the parts may be bound, one uponanotherin such manner that there shall be, practicably, no spaces forthe movement or admission of air currents underneath the metal plates.

I am aware that nails have been used for holding the metal casing inposition relative to a wooden core and interposed non-conductingmaterial; but it is obvious that in carrying out my invention theemployment of bolts or similar clamping devices which pass through thecore, the non-conducting mate rial upon opposite sides of the core, andthe metal casing plates outside of the non-conducting material, is veryimportant as regards enabling me to keep the component parts of thefabric so compressed one upon another as to prevent the movement ofaircurrents within the metal casing'even though the core becomescharred; from the fact that parts of the clamps overlap and lie outsideof the adjacent surfaces of the casing and therefore cannot be loosenedby any tendency on the part of the materials to warp or otherwise changeposition under various conditions of temperature. I

It is obvious that although nails which pass through the casing upononeside of the structure and penetrate the core with intent to be heldfrom withdrawal by reason of their frictional contact with the core, butare liable to be loosened byshrinking orcharring the core, do notoperate in the same manner nor perform the same function as do my clampswhich cannot be loosened by any of the changes of condition of the corewhich will be liable to materially impair the usefulness of nails oranalogous devices. In order to facilitate properly binding these partstogether I prefer to make the bolt holes through the flanges d (1 closeenough to the intermediate section D, so that it will be necessary topress those intermediate sections and the asbestus underneath them quitefirmly against the edges of the board in order that the bolt holes inthe flanges shall register with those in the sheets or plates E E andthe wooden central plates or strips, as will be readily understoodwithout further explanation. So, also, in order to avoid anyobjectionable projection of the clamping devices beyond the outer facesof the metal sheets or plates I propose, under some circumstances, tocounter-sink the holes in the metals, strips and sheets and usecorrespondingly shaped bolt heads and nuts of such form and size thatwhen properly screwed up their outer faces will be substantially flushwith the adjacent metal, as is indicated at c c Fig. 7; or rivets may beused as indicated at b b Fig. 7.

In case it is desired to use moldings or headings or other form ofornamentation of so elaborate a character that it be found impracticableor undesirable to stamp or swage the opposing sheets E to correspondingshape, part of the ornamentation may be applied to the outer surface ofthese sheets after they have been bolted or riveted in place. In fact,this method of procedure will sometimes be found very advantageous,especially when it is practicable to apply such supplemental orauxiliary ornamental parts so as to cover bolt heads or rivet heads. Infact,when such supplemental parts are made of metal they may be solderedto the sheets E.

Referring particularly to Figs. 3 and 8, Q, Q, are the jamb liningsrabbeted as at q, q, where the door is to be hung. In case this frame orjamb lining is, as I prefer it should be, constructed with a combinationof the asbestus sheet 0 and metal sheets D, E, both the metal and theasbestus may be cut out to receive the hinge-leaves, care being takenthat the combined thickness of the asbestus and metal be about that ofthe hinge-leaf which is to be embedded therein; and I prefer to cut outthe metal in such shape that the edges of the cut sections may be turnedinward over the edges of the asbestus sheet to facilitate making smoothand finished joints at such places. While, under many conditions, thesheet metal may be, by the use of suitable tools, properly bent by handlabor; yet I prefer to use machinery for this purpose in order to obtaina morelaccurate shaping of parts. RR are dressings, of which those shownare of comparatively plain pattern in cross section, having a simpleogee molding at its inner edge where it joins the jamb lining; with,preferably, an architrave S, and frieze T, surmounted by a cornice T.These latter I propose to make of sheet metal on account of the somewhatelaborate design which is desirable for such purpose; but, under manycircumstances the architrave, the frieze, and

the cornice above the door may be omitted; in which case the dressings RR are continued across the tops of the doors with miter-joints as iscustomary.

While I have only illustrated my invention as applied to doors and theparts which are ordinarily immediately adjacent thereto, it is evidentthat practically the entire woodwork trimmings of an apartment such, forinstance, as the door-sills, the skirting board and its base molding,the sub base above the dado, when ,one is used, as well as the windowsills and frames may be made of the same composite materials; togetherwith many if not the entire parts of inside blinds, mantels, and suchother trimmings as are usually made of wood. Thus it is practicable, bythe use of my invention, to not only prevent fire from passing throughdoorways, but also to render practically the entire woodwork within aroom substantially fire-proof. I,

It is obvious that an ornamental ceiling can be constructed in panel andother forms and rendered fire-proof when built in accordance with myinvention. may be embodied outside in ornamentations such as windowsills and caps and cornices where it is desirable that, even thoughsubjected to such heat as will char the wood throughout, the parts shallretain their shape whereby they will serve to prevent the passage ofheated currents. I 1

One of the advantages which is incident to the use of wood as thecentral sheet or strip is due to the fact that, even though it beconverted'throughout into charcoal, it will still serve as anon-conductor and preserve its form and dimensions under any strain,shock, or change of temperature or change of condition as regardsmoisture to which it will ordinarily be subjected.

It is obvious that my invention is adapted for usein the construction ofstudding in partitions; especially in cases where metal lathing is to beemployed, from the fact that owing to the characteristics of charcoal,as above indicated, and that in the case of studding a stud isrectangular in cross section and is surrounded by a sheet metal tubewhich is also rectangular in cross section and its sides are protectedagainst collapsing or springing in either direction laterally by beingbolted to the central strip, the studding will retain its strength inboth directions in a very large measure even though subjected to heatofsuch intensity and duration as to char it entirely through. Thus it isevident that, with studding of this character, and metal lathing, apractically fire proof partition can be made. The same thing is true, ina very great degree, in the case of stairways, from the fact that boththe treads and risers are supported against downward pressure as are thestuds against lateral pressure; and further than this, by reason of therisers serving as trusses to support the treads no amount So, also, theinvention of charring would probably weaken the staircase so that itwould give way under any weight which could ordinarily be imposed uponit. The fire proof plates, slabs, or panels which can be thus producedby my inven tion may also be advantageously used in the construction ofclosets within apartments; also for boxes and chests by the use ofscrews or bolts or straps. They can also be used for roofs, for whichpurpose they are specially adapted because the rafters embodying theinvention will ordinarily support the roof from falling in even thoughcharred, because a roof which is strong enough before a fire to supporta body of snow will support its own weight even though subjected tosevere heat. The same material may be used as a fire screen; especiallywhere flexibility is required because the edges of the strips or platesmay be hinged together in such manner that a screen, shutter, or curtainlike structure, such, for instance, as is sometimes made to interposebetween a burning building and an adjacent one which it is desired toprotect,

may be folded up into comparatively small compass.

It is apparent that the results which are accomplished by the use of myinvention could not be attained by a structure in which a granular orpulverized material such as earth or ashes are employed asnon-conducting material for many reasons. In the first place it would beimpossible to so dispose a packing of that sort between the metal platesand the core in such manner as to practically fill the space betweenthem under such a degree of compression as will prevent spaces for aircurrents. Again after a short lapse of time such pulverulent materialwill settle and pack by reason of its weight, thus further increasingthe size of the air spaces. These objections would be met with in anincreased degree whenever the article thus produced be a door or anyother thing which is liable to be jarred frequently; and of course noflexibility exists in granular material which would permit its beingbent to conform to surfaces of irregular configuration and havingalternate raised and sunken portions.

While I prefer to make the central or intermediate section A, B, of woodyet I do not wish to be limited to that material; because when too largeplates are not required and they will not be subjected to too greatstrain other vegetable or fibrous substances may be employed.

While I prefer asbest us as the non-conducting fireproof layer or sheet0, yet I do not wish to be limited thereby, because some of thesubstances which are employed for a similar purpose in, for instance,the walls of fireproof safes, may be substituted therefor and securesome of the advantages which are incident to my invention. For instance,the scantling to be used for studding and the joists for roof supportsmay be made by placing them, respectively, about centrally within metaltubes or jackets of proper size, and then filling the annular spacesbetween the jackets and the central strips with a semiliquid or pastymass of the requisite consistency.

While I have thus described the best means known to me for carrying outmy invention, 1 do not wish to be limited to the precise details abovegiven; because many modifications will readily suggest themselves to anyone who is familiar with the art without going outside of the spirit ofmy improvement.

What I claim "is 1. A composite fire-proof material forms in sheets orstrips, and comprising a core of fibrous vegetable material, an outercasing of sheet metal, interposed flexible non-conducting material, andclamping devices extending through the core and the metal casings onopposite sides of the core, and adapted to bind said casings to eachother and to the core and non-conducting material, substantially as setforth.

2. A composite fire-proof material formed in sheets or strips, andcomprising a core of fibrous vegetable material, an outer casingcomposed of metal sheets disposed to overlap at their edges, interposedflexible sheets of non-conducting material, and clamping devices forbinding the parts together,substantially as set forth.

3. A composite fire-proof material formed in sheets or strips, andcomprising a core of fibrous vegetable material, metal U shaped casingplates at the edge of the core, metal casing sheets at the sides of thecore, an interposed flexible non-conducting material, and clampingdevices for binding the parts together, substantially as set forth.

4. A composite fire-proof material formed in sheets or strips, andcomprising a core of vegetable material having a surface formed ofalternate raised and sunken portions, an outer casing of sheet metalhaving corresponding raised and sunken portions, an interposed sheet offlexible non-conducting ma terial of substantially uniform thicknessthroughout, and clamping devices for binding the parts together,substantially as set forth.

5. The herein described composite fireproof door, comprising acore offibrous vegetable material disposed to form panels,stiles and rails,outer casings of sheet metal disposed to form corresponding panels,stiles and rails, edge casings which are U-shaped in cross section,interposed sheets of asbestus which are flexible, and clamping deviceswhich pass through the opposite metal casings and are adaptedto compressthe parts together and bend the asbestus sheets into conformation withthe configuration of the door, substantially as set forth.

6. The herein described composite fireproof door, comprising a Woodencore disposed to form panels, stiles, and rails, one stile having hingeseats formed in the edge, sheet metal casings disposed to formcorresponding panels, stiles and rails, the sheet metal being turnedover the hinge seats and fitting closely thereto, an interposed sheet offlexible non-conducting material, and clamping devices for binding theparts together, substantially as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

'EZEKIEL M. PRITOHARD. Witnesses:

J. HOMER HILDR-ETH, WM. MARKUSKE.

